By detecting the temperature of oil circulating through an internal combustion engine with an oil temperature sensor provided on the internal combustion engine, it is possible to accurately gain an understanding of, for example, the warming-up state of the internal combustion engine.
Known examples of such oil temperature sensor mounting structure for an internal combustion engine include: structure (1) in which a temperature sensor for detecting the temperature of oil in an oil return passage is mounted to a lower portion of a cylinder of the internal combustion engine together with a sensor cover that protects the temperature sensor (for example, see JP-A No. 2004-293348; and structure (2) in which a temperature sensor for detecting the temperature of oil in crossing oil circuits provided in a cylinder head is mounted to a side of the cylinder head of the internal combustion engine (for example, see JP-A No. 2011-1423).
JP-A No. 2004-293348 discloses the structure in which the temperature sensor is mounted on a lower position in the internal combustion engine. Furthermore, in order to protect the temperature sensor from scattering stones or the like, a sensor cover that protects the temperature sensor from the front is mounted to the cylinder. Therefore, the number of components, such as the sensor cover and bolts for fastening the sensor cover to the cylinder, is increased. Also, to mount the sensor cover, it is necessary to provide a sensor cover mounting portion on the cylinder.
In JP-A No. 2011-1423, the temperature sensor protrudes laterally from a cylinder head, thereby likely to result in a deterioration in appearance. Even if a covering member for covering the temperature sensor is provided, the covering member needs to be widely spaced apart laterally from the internal combustion engine to prevent its interference with the temperature sensor. If the covering member is further laterally disposed in this manner, an increase in size of a vehicle body is caused.
Accordingly, the present invention has been made in view of the foregoing, and an object of the present invention is to provide an An oil temperature sensor mounting structure for an internal combustion engine is provided which is capable of improving the appearance while protecting an oil temperature sensor with a simple structure and further capable of miniaturizing and downsizing a vehicle body.